Answer :

The launch of Sputnik 1, the first artificial satellite created by the USSR, generated a big reaction from the United States. The United States wanted to get a technological advance to the Soviet Union, as they were currently in a period of the Cold War where the arms races and space race was heavy. It also created the effect across the United States that the US was not the most technologically advanced country and that the Soviet Union was not as backwards as it had been stated as being.
MrZieleniewo

Answer:  The US took steps to catch up and surpass the Soviets in the space race.

Details:

The Sputnik satellite was sent into orbit by the USSR on October 4, 1957.  The Soviets announced its mission as a scientific one, to study the solar system.  In the Cold War atmosphere, of course, Americans were wary of what other motives the USSR might have had.  The Soviets launched Sputnik 2 in November, 1957, with a dog on board.  The USA scrambled to get its own satellite program operational, launching the first US satellite, Explorer, on January 1, 1958.

The National Aeronautics and Space Administration (NASA) was founded in July, 1958, to continue the United States' advance in space technology.